Search PubMed⌕ Search

Biomedical subjects

T Bates

Publications and source records attributed to T Bates.

At least 73 records · Page 4Linked to original sources
PubMed1991

Simplified quantitative estimation in vitro of lymphocyte radiosensitivity applied to patients with chronic lymphocytic leukaemia.

Lymphocyte survival changes observed at 1, 2 and 3 days as responses to 3 doses of ionising radiation in vitro (40, 100, and 500 cGy) are analysed by computer according to a simple (single cell population) mathematical model. Intrinsic radiosensitivity, the susceptibility to lethal injury, which is expressed as the D37 value (the radiation dose permitting 37% survival), is estimated separately from the kinetics of subsequent death of lethally-irradiated cells (expressed as their half-life, or t1/2 value). Among the 35 patients with B-cell CLL studied (15 were never treated), both parameters varied widely and independently of one another. t1/2 ranged from 9-200 h and above, D37 from 14-500 cGy or above. Twenty-three patients were deemed 'radiosensitive' (D37 below 110 cGy). D37 level did not correlate with treatment status, mode of treatment, clinical staging (Rai) or lymphocyte count. With some exceptions, D37 remained relatively constant for individual patients with increasing duration of disease or alterations in treatment status. The assay method may prove useful as an aid in predicting response to low-dose splenic irradiation (SI) in CLL.

B-Lymphocytes↗
PubMed1990

Treatment of carcinoma of the breast with high dose oral medroxyprogesterone acetate: does increased bioavailability improve the therapeutic ratio?

Medroxyprogesterone acetate (MPA) is regarded as a valuable hormonal therapy for metastatic breast cancer. The drug is manufactured by more than one pharmaceutical company, and one particular brand of oral MPA (Provera Tablets, Upjohn) has been reformulated to incorporate micronized particles, providing significantly enhanced bioavailability. The response rate and side-effect data from a pilot study, which used the old formulation Provera Tablets 100 mg at a dosage of 800 mg/day in 28 patients with recurrent breast cancer after treatment with tamoxifen, are compared with those from another study in which 59 similar patients received 800 mg/day of new formulation Provera Tablets 200 mg. Neither of these studies, conducted in the United Kingdom, has previously been published. The response rates were similar in both studies, but there were higher incidences of significant weight gain and increased blood pressure in those patients treated with the new formulation. These side effects have been noticed by other workers employing new formulation MPA at a dosage of 800 mg per day, while it has been reported that reducing the dosage to 400 mg perday is accompanied by a lower incidence of side effects, without affecting the response rate. It is concluded that the increased serum levels of MPA, made possible by the micronized product, do not favourably influence the response of metastatic breast cancer to therapy, but may be associated with a higher incidence of side effects. Reducing the dosage of the new formulation MPA to 400 mg/day may allow a more acceptable side-effect profile, without loss of therapeutic efficacy. Such a dose reduction would make this brand of MPA more cost effective.

Administration, Oral↗
PubMed1989

Timing of prophylactic antibiotics in abdominal surgery: trial of a pre-operative versus an intra-operative first dose.

When prophylactic antibiotics are used in abdominal surgery it is customary to give the first dose before the operation. Whilst intra-operative antibiotics may be effective in elective surgery, there may be an advantage to starting pre-operatively when there is already an infective focus such as appendicitis. Antibiotics started pre-operatively (group P) have been compared with antibiotics started after initial abdominal exploration (group T). Three intravenous doses of 500 mg metronidazole plus 1 g cephazolin were given in a randomized, double-blind study of 700 emergency and elective high-risk abdominal operations. Antibiotic plasma concentrations at the end of the operation were significantly lower in group P but lay well within the therapeutic range. Wound infection rates, which included minor and delayed infections, were similar in both groups (group P, 57 of 342, 16.7 per cent; group T, 55 of 358, 15.4 per cent; 95 per cent confidence intervals for the difference being -4.1 to +6.7 per cent. In appendicitis, wound infection rates were 12.1 and 13.9 per cent for groups P and T respectively. However, non-fatal deep sepsis was more common in group P (nine cases) than in group T (two cases) (chi 2 = 4.9, P less than 0.05). Postoperative infection was twice as common in obese patients whose body mass index (BMI) was greater than or equal to 26 (39 of 132, 30 per cent) than in thin patients whose BMI was less than 24 (41 of 288, 14 per cent; chi 2 = 13.8, P less than 0.001). This study failed to show any advantage to starting antibiotics pre-operatively, even in appendicitis.

Abdomen↗
PubMed1989

Response of breast carcinoma to endocrine therapy predicted using immunostained pelleted fine needle aspirates.

Fine needle aspirates from 82 patients with breast carcinoma were fixed in methacarn, double embedded in agar or gelatin, and then in paraffin wax. Sequential sections were stained with monoclonal antibodies to the oestrogen receptor-related protein P29 (antibody D5), carcinoembryonic antigen (CEA), epithelial membrane antigen (EMA) and cytokeratin (CAM 5.2). Sixty-one of 82 (74%) aspirates provided sections suitable for immunostaining. Twenty-six (43%) were D5 positive, 23 (38%) CEA positive, 59 (97%) EMA positive, and 54 (89%) CAM 5.2 positive. Twenty-six of these patients were treated with some form of endocrine therapy. Twelve (46%) showed positive staining for D5. Eleven (92%) of the 12 D5-positive patients responded or had static disease, and 8% progressed. Of the 14 D5-negative tumours 43% responded or remained static, and 57% progressed. The difference in response between the D5-positive and the D5-negative tumours was significant (P less than 0.05, Fisher's exact test). There was no correlation between staining for CEA, EMA or cytokeratin and response to endocrine therapy.

Adult↗
PubMed1989

Advanced breast cancer. A randomised trial of epidoxorubicin at two different dosages and two administration systems.

Sixty-two women with advanced breast cancer have been entered into a randomised trial comparing bolus injection with 24-h infusion of epirubicin given as a dose of either 20 mg or 40 mg weekly, of which 57 patients are eligible for analysis. Bolus injection proved significantly more successful than prolonged infusion in response rate, time to first event and survival. No significant differences appeared between the two doses using these measures, however 40 mg weekly was significantly more toxic than 20 mg weekly. Epirubicin given as a weekly 20 mg bolus injection appears both effective and relatively free from toxicity.

Breast Neoplasms↗
PubMed1988

Failure of kindling to alter susceptibility to kainic acid.

In this study, the interaction between electrical kindling and kainic acid seizures was investigated. Prepubescent male rats were kindled using hourly, suprathreshold stimulations. Two days later the kindled rats and their non-kindled controls received systemic injections of either 6, 10, or 17 mg/kg of kainic acid. No differences in response to kainic acid were seen between the two groups. These data demonstrate that the kindled brain does not uniformly exhibit a lower seizure threshold to all convulsants, but is dependent on the agents subsequently used to induce the seizures.

Animals↗
PubMed1988

Breast cyst type does not predict the natural history of cyst disease or breast cancer risk.

The sodium (Na) and potassium (K) concentrations were measured in the fluid of 169 breast cysts aspirated from 101 consecutive patients presenting to a single clinic. The Na/K ratio was used to define cysts as either apocrine (Na/K less than 3) or flattened (Na/K less than 3) in type. There was no consistency in the type of cyst for individual patients. Cyst type was not predictive of further cyst development, neither was a particular cyst type associated with the development of, or a history of, breast cancer.

Age Factors↗
PubMed1988

Simplifying infusion chemotherapy: preliminary communication.

A low-intervention policy for Hickman catheter maintenance has been evaluated and found to be safe and cost effective. A simple, lightweight, disposable device has been used for 24-hour ambulatory home infusion. Implementation of this policy as part of a prospective randomized trial of single-agent chemotherapy in advanced breast cancer has demonstrated that slow intravenous infusion reduces the acute toxicity of epirubicin when compared with bolus injection.

Breast Neoplasms↗
PubMed1986

A preliminary study of low-dose splenic irradiation for the treatment of chronic lymphocytic and prolymphocytic leukaemias.

21 patients, 18 with chronic lymphocytic leukaemia (CLL) and 3 with prolymphocytic leukaemia (PLL), all B-lymphocyte origin and with progressive disease, were treated with a regime of low-dose splenic irradiation (SI). All patients experienced a rapid relief of disease-related symptoms. Following SI the total lymphocyte count (TLC) was markedly reduced in 18 patients. Partial to complete regression of splenomegaly occurred in 9 patients. Pre-existing anaemia of production failure type improved in 6 patients and as a result the haemoglobin rose to normal or near normal levels. SI caused the loss of T-, B- and Null-lymphocytes, but the loss of B-lymphocytes predominated. CLL/PLL became quiescent for long periods in 9 patients (CLL = 8; PLL = 1) but remained progressive in the other 9, all CLL. SI had no demonstrable effects on TLC, splenomegaly or anaemia in the 3 remaining patients (2 CLL, 1 PLL). The treatment was well tolerated by all, and side effects were almost absent. Transient reduction of neutrophils and platelets occurred commonly. No patient with initially normal neutrophil and platelet counts developed irreversible neutropenia or thrombocytopenia. In view of these effects, the ease of administration and the lack of side effects, further evaluation of low-dose SI, particularly in comparison with other regimes, seems worthwhile.

Adult↗
PubMed1985

Oral pemoline kinetics in hyperactive children.

The time course of pemoline in plasma was investigated in seven prepubescent boys with attention-deficit disorders who were hyperactive. Maximum plasma concentrations of 4.3 +/- 1.0 mg/L were reached 2.8 +/- 1.8 hours after a single, 2 mg/kg oral dose of pemoline, followed by a monoexponential decline in plasma concentration over time. Mean t1/2 and total body clearance of pemoline were 8.6 hours and 0.65 ml/min/kg. The 600% interindividual variation in elimination t1/2 and the 300% variation in total body clearance of pemoline may explain the unpredictable nature of its dynamics and associated neurotoxicity in some cases.

Absorption↗
PubMed1984

Obstructing/perforated carcinoma of the left colon treated by resection and the formation of a double colostomy.

Forty patients presenting with obstructing left colon tumours between 1975 and 1980 were treated by a modified Paul-Mikulicz resection. The hospital mortality was 5 per cent. Subsequent mortality was largely related to the stage of the tumour at presentation and was not higher than that to be expected after an elective resection. In 21 patients the procedure was palliative and 16 of these patients later died. The quality of palliation was reasonable in 80 per cent and poor in 20 per cent. Despite the need for a second hospital stay to close the colostomy, time in hospital accounted, on average, for less than one-tenth of the remaining lifespan in those having a palliative resection.

Aged↗
PubMed1984

Gall stones and mortality: a study of all gall stone related deaths in a single health district.

In a prospective study of gall stone related deaths in a single Health District, the biliary tract was examined at necropsy in 1701 cases and 8078 death certificates were searched. Gall stones were identified as the cause of death in only 21 cases (0.26%) but in 291 subjects found to have gall stones or cholecystectomy at necropsy, the mortality was 3.4%. The necropsy prevalence of gall stones in the adult population was 17.1% but nine out of 10 subjects with gall stones had not had a cholecystectomy and women were three times more likely to have had their gall stones removed than men. There were five postoperative deaths (mean age 60 years) with an operative mortality for cholecystectomy in the district of 1.2%. Death due to unoperated gall stones was identified in 16 subjects, most of whom were very elderly women (mean age 81) but carcinoma of the gall bladder was only found in one woman of 90 with gall stones. The prevalence of gall stones rose with age in both sexes but the cholecystectomy rate per head of population at-risk declined sharply in the seventh decade in women and the eighth decade in men. There are a large number of people with unoperated gall stones in the population but gall stone related deaths are very uncommon. The cholecystectomy rate in Britain, however, seems to be rising and it is suggested that if this trend continues there may be an increased number of deaths.

Adult↗
PubMed1983

Metronidazole v. cefoxitin in severe appendicitis--a trial to compare a single intraoperative dose of two antibiotics given intravenously.

In severe appendicitis, the effect of a single intravenous dose of metronidazole (500 mg) was compared with cefoxitin (1 g). The antibiotics were given by random allocation once the diagnosis had been established at operation. In the metronidazole group, 5 out of 48 patients developed a wound infection whilst in hospital compared with 13 out of 48 in the cefoxitin group (P = 0.036). However, 57% of wound infections became apparent after the patient went home and the overall infection rates were similar. The mean length of postoperative hospital stay was 5.0 days in the metronidazole group and 6.8 days in the cefoxitin group (P = 0.052), but of those who did develop a wound infection, the length of stay was almost double in the cefoxitin group. Anaerobic organisms were cultured from the wound in 7 out of 15 patients who received cefoxitin but in none of 5 patients in the metronidazole group. Whilst metronidazole only delayed the discharge of pus from the wound, it did seem to reduce the severity of infection. Cefoxitin appeared to be less effective, given as a single intravenous injection at a dose of 1 g.

Adult↗